In a 600-word post, Brad questioned the credibility of an online petition on Smith's website, urging the administration of President Barack Obama to require labeling of biotech foods. He called the petition "sheer political theater" and prodded the activist for purportedly being a yogic flying instructor.

More than 30 comments followed in the next few weeks. On one level, the exchange was just another online debate about GMOs. But this one was notable because of who initiated and hosted it: Monsanto Co.